Method of vaporizing



Jan. 24, 1933. E E 1,895,220 I METHOD OF VAPORIZING Filed Aug. 15, 19272 Sheets-Sheei 1 I N VEN TOR.

A TTORNEYS.

Jan. 24, 1933. J, J, GREBE 1,895,220

METHOD OF VAPORIZING Filed Aug. 15. 192 2 She ets-Sheet 2 I N VEN TOR.

To/271 I Grew A TTORNEYS Patented Jan. 24, 1933 UNITED STATES JOHN J.GBEBE, OF MIDLAND, MICHIGAN, ASSIGNOR T0 or MIDLAND, MICHIGAN, A

union or THE DOW CHEMICAL COMPANY, CORPORATION 01' MICHIGAN vuomzmeApplication filed August 15, 1927. Serial 170,212,913.

The principle of the invention'is herein explained and the best mode inwhich I have contemplated applying that. principle so as to distinguishit from other inventions.

ere power generation is more articularly concerned with energy transfer1n fluids at very high pressures, it is desirable in some circumstancesto carry as high a temperature as possible. Especially in the case ofsteam, the advantages of very high pressures may be furthered if thetemperatures be proper and adequately maintained.

To the accomplishment of the foregoing and related ends, the invention,then consists of the features hereinafter fully described, andparticularly'pointed out in the claims, the following description andthe annexed drawings setting forth in detail certain structure embodyingthe invention, such being illustrative however of but a few of thevarious ways in which the principles of the invention may be employed.

In said annexed drawings Fig. 1 is a semi-schematic showing of a plantlayout embodying the invention; and Fig. 2 is a similar view of amodification.

In its general aspectsthe invention contemplates means for generatingvapor under pressure, more usually steam, and a heater for a higherboiling point fluid, and means for temperature balancing heat transferbetween the two fluids. and a further means for applying heat to thefirst-named fluid by means of furnace temperatures permitting productionof vapor temperatures approaching furnace temperature without requiringa correspondingly high temperature in the equalizer.- As illustrated inFig. 1, an advantageous equipment may comprise a fur nace 1 heated byany suitable means, for. ex-

ample bv powdered fuel supplied by a feeder 2. Within this furnacechamber is a generator for steam or the like, comprising a tubularsystem 3. Located also in exposure to the furnace conditions is a heaterfor a fluid higherboiling point agent, for example diphenyl oxide, thisheater comprising preferably a tubular system 4. The tubular system 4 isin communication with a drum or the like 5, and passing through the drumis a.

conduit 6, preferably in multi-coil form, this conduit being connectedwith the generator system 3 on the one hand and on the other handconnecting with a tubular system 7 exposed in the furnace chamber,preferably in the path of the gases on their way to the stack. From thefurnace-heated tubular system 7, a. pipe 8 leads to the point of usageof the steam or the like, in the illustration this comprising a turbine9 for high pressure and a second stage turbine 10, these being connectedto a dynamo or other load 11. The exhaust from turbine stage 9 passes byconnection 12 to a heat exchanger 13, and thence by connection 14 to thesecond stage turbine 10. From the latter, a connection 15 leads to aheat exchanger 16 and from thence a connection 17 in turn leads to afurther prime mover, preferably a turbine 18. A condenser 19 may bearranged to receive exhaust from such final turbine and in turn thecondensate may then be forwarded by a pump 20 to a first stage heatercoil system 21 in the outlet section of the furnace, and from this, aconnection 22 leads to the main generator a tubular system 3. t

A higher boiling point agent in fluid form may be-conducted from thedrum 5 by a connection 23 to a jacket 24'about the turbine 9, and thencebyconnection 25 to the heat exchanger 13, and by a connection 26 furtherto a jacket 27 about the second stage turbine 10. From the latter, aconnection 28 leads to the exchanger 16, and a connection 29 in turnleads therefrom to :1V jacket 30 about the steam pipe 17. Return of thehigher boiling point agent may be provided by a connection 31 leadingthrough a pump 32 to a return pipe 33 to the boiler system 4.

In operation, as will be readily understood from the foregoing, steam isgenerated in the boiler 3, and such equipment may particularly favor thegeneration of steam under very h gh pressures, for instance of usablemagnitude even over 1200 pounds per square inch. From the generator 3,it will be noticed that the steam passes through the interchanger orbalancer drum 5, and thence through the furnace heated tubular system 7where a final booster heating is received. From this, the

and second stage turbines 9, 10, and the final turbine 18. Thetemperature of the turbines 9 and as will be noted is further maintainedby the jackets 24, 27 supplied by the high boiling point agent from theboiler system 4 therefor; and heat exchangers 13 and 16 in theinter-stages provide reheating 1 in an advantageous manner. From thefinal point of usage in the last turbine, the exhaust goes through thecondenser 19 and is thence forwarded by the pump 20 to the first stageheater 21 of the boiler'system in the furnace. An accumulator 34 may beincluded in the boiler feed line if desired, for regulating the feed tothe boiler. Also heat exchangers may be included in the line, as may bedictated by convenience. All these being immaterial to the presentinvention, further detail is unnecessary. r

In'the form shown in Fig. 2, a furnace chamber 1' is heated by anysuitable means, for example-as shown, a powdered coal system havingfeeder 2', and arranged in the furnace chamber is a boiler or generatorfor steam or the like, such generator comprising a bank of tubes 3'connected with an inlet header 3a and extending through an interchangerdrum 5' whence by return bends, the tubes continue'as at 7 back throughthe fur nac'e, particularly along the walls thereof in the primarycombustion zone, and thence leading as connections 8' tothe point of.usage, for instance, the first-stage prime mover or turbine 9', and thesecond stage prime mover or turbine 10'. A final stage prime mover orturbine 1.8 may also be arranged.

The heat interchanger or balancer 54 is arranged to receive the highlyheated fluid higher boiling point agent from the boiler or tubularsystem 4 mounted in the furnace, and from the interchanger drum 5 aconnection 23 leadsto an exchanger 13 for reheating the exhaust from theturbine stage 9', a

connection 12 forwarding such exhaust to the exchanger, and a connection14' leading the steam in turn to the second stage turbine 10. A furtherexchanger 16' may be applied between the turbine stages 10 and 18, suchexchanger receiving the exhaust steam by connection 15' from the turbine10', and having a connection 17 in turn to the turbine 18'.

From the exchanger 13, the diphenyl oxide 1 or other agent of highboiling point may pass by connection 26 to a jacket 27 about the turbine10, a connection 28 thence leading to the heat exchanger 16, and fromthence a return pipe 81 tothe pump ,32. From the latter, a return line33' leads to the boiler system 4'.

With such installation analogously, steam or the like is generated inthe boiler system 3', and passes through the interchanger or balancer 5Where it is in heat transfer relationship with the highly heated agentof high boiling oint from the boiler system 4'. Thence-the steamproceeds through the heater tubes 7 exposed inthe furnace preferably ina location to receive the radiant heat of the furnace, and thence thushighly heated, steam under high pressure, which may be for instance onthe order of 1200 to 1500 pounds, and with any degree of superheatfeasible and desirable, as for instance a temperature 0 950 F. mayproceed to the point of usage, in the illustrative form shown, thiscomprising the first and second turbines 9', 10, and the final turbine18'. Between the turbine stages, reheating is provided by the exchangers13', 16 which are supplied by boiling point agent. From the finalturbine 18, the exhaust may lead to a condenser 19 and thence by pump20' to the boiler 3. An accumulator 34 may be arranged in the line ifdesired.

While the arrangements as shown, include various refinements ofmulti-stage prime mover use, and interstage reheating by exchangers,jackets, etc., it will be understood that such refinements may beomitted, and the utility of the invention may be realized in itssimplest terms, and while particularly advantageous where applied tosteam plants operating atvery high pressures and temperatures, theadvantages of the invention may be realized in degree also with lowerpressures.

Instead of steam, in some instances the primary fluid to be used may bealcohol, acetone, chlor-organic compounds, organic hydrocarboncompounds, inorganic compounds, etc. And as high boiling point fluid, Imay employ available high boiling point substances of stable charactersuch as diphenyl oxide, most usually, and in some instances also pyreneor stable hydrocarbons, inorganic substances as mercury, aluminumbromide, tin bromide, etc.

Other modes of applying the principle of the invention may be employed,change being made as regards the details disclosed, provided. the stepor means stated in any of the following claims, or the equivalent ofsuch, be employed.

- I therefore particularly point out and distinctly claim as myinvention-:

1. In a method of evaporating a low'boiling liquid in one pass underpresure, the steps which consist in evaporating a substantial portion ofsaid liquid with hot products of combustion, passing the fluid' productsof said evaporating step in temperature balancing heat transfer relationwith a heated fluid of higher boiling point, and then subjecting the sogenerated vapor of the low boiling point liquid to heat from a furnace.

y 2. In a methodof one-pass evaporation of water under pressure, thesteps which con the- H highly heated diphenyl oxide or like high sist inevaporating a substantial portion of I said water by means of heat froma hot fluid, subjecting the so heated fluid products of saldevaporation'step to a temperature balancing heat transfer with anotherheated fluid of higher boiling pointthan water, and then further heatingthe so generated steam.

3. In a method of evaporating water under I pressure in one pass, thesteps which consist in evaporating a substantial portion of said waterby means of hot products of combustion, subjecting the so produced steamto temperature balancing heat transfer with hot diphenyl-oxide, and isen further heating the steam by furnace heat.

4. In a method of one-pass rapidevaporation of water under pressure, thesteps which consist in evaporating a substantial portion of said water bmeans of hot products of tion.

the so produced fluid products combustion, sub ecting the so producedsteam to a temperature balancing heat transfer with aheated fluid ofhigher boiling point than water and then further heating the sogeneratedsteam with. hot products of combus- 5. In a method of one-passevaporation of water under high pressure, the steps which consist ininitially supplying heat from hot products of combustion to evaporate atleast a major portion of said water, subjecting of said evaporation stepto a reversible heat flow temperature balancing heat transfer with aheated fluid of. higher boiling point to insure a completion ofevaporation of the water and its delivery at relatively uniformtemperature, and subsequently supplying a further amount of heat to saidsteam to superheat same.

j, Signed by me this 2nd day of -Aug., 1927.

JOHN J. GREBE.

